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    <title>Document</title>
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<body>
    <script>
        //从以下学员名单中随机选出4个学员：

        // console.log(Math.floor(Math.random() * arr.length));
        let arr = ["鹿晗", "王俊凯", "蔡徐坤", "彭于晏", "周杰伦", "刘德华", "赵本山"]
        for (let i = 0; i < 4; i++) {
            arr = ["鹿晗", "王俊凯", "蔡徐坤", "彭于晏", "周杰伦", "刘德华", "赵本山"]
            let j = Math.floor(Math.random() * arr.length)
            let a = arr[j]
            arr.splice(j, 1)
            document.write(a)
        }
        //注意：不要有重复的学员（封装函数）
    </script>
</body>

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